Endoprosthesis of shoulder joint

ABSTRACT

An endoprosthesis of the shoulder joint, comprising a pin adapted to be fixed in the medullary channel of the humerus, provided at its end with a spheroidal head, and a shaped crown adapted to be fixed on the articular process of the scapula, and provided with a spherical socket for interaction with the head of the pin, to form an articulated joint, on passing the pin through the socket. Walls of the crown have edges split by recesses into segments which, when compressed, enable osseous tissue to be tightly embraced by the walls of the crown.

United States Patent [1 1 Golyakhovsky I ENDOPROSTHESIS OF SHOULDER JOINT [76] Inventor: Vladimir Julievich Golyakhovsky,

ulitsa Krasnoarmeiskaya, 25, kv. 57, Moscow, USSR.

22 Filed: Dec. 30, 1971 211 Appl. No.; 214,295

[52] US. Cl. 3/1, 128/92 C [51] Int. Cl. A6lf 1/24 [58] Field of Search..... 3/1; 128/92 C, 92 CA, 92 R [56] References Cited UNITED STATES PATENTS 3,656,184 4/1972 Chambers 3/1 3,670,724 6/1972 Bosacco 3/1 2,947,308 8/1960 Gorman 128/92 CA 2,719,522 10/1955 l-Iudack 128/92 CA FOREIGN PATENTS OR APPLICATIONS 1,047,640 7/1953 France 128/92 C OTHER PUBLICATIONS McBride Acetabulum Cups and Urist Hip Sockets,

Vitallium Surgical Appliances", Catalog Austenal Co., New York, N.Y., page 30, 1964. Austin Moore Straight Stem Self Locking Hip Prosthe- [451- Apr. 16, 1974 ses (Narrow) and (Extra Long), Vitallium Surgical Appliances", Catalog, Austenal Co., New York, N.Y., page 21, 1964.

Vitallium Surgical Surgical Appliances Catalog,

Austenal Surgical Products, I-Iowmet Corp., N.Y.,

N.Y., 1964, FIG. No. 6983/Moseley, Glenoid Rims, page 55 relied upon.

Primary Examiner-Richard A. Gaudet Assistant Examiner-Ronald L. Frink's Attorney, Agent, or Firm-Eric H. Waters [5 7] ABSTRACT An endoprosthesis of the shoulder joint, comprising a pin adapted to be fixed in the medullary channel of the humerus, provided at its end with a spheroidal head, and a shaped crown adapted to be'fixed on the articular process of the scapula, and provided with a spherical socket for interaction with the head of the pin, to form an articulated joint, on passing the pin through the socket. Walls of the crown have edges split by recesses into segments which, when compressed, enable osseous tissue'to be tightly embraced by the walls of the crown.

7 Claims, 3 Drawing Figures ENDOPROSTI-IESIS OF SHOULDER JOINT The present invention relates to the sphere of surgicalpractice and has particular reference to an endoprosthesis of the shoulder joint, applicable in an operative mobilization of the shoulder joint.

No endoprostheses of the shoulder joint are known to be used in surgical practice nowadays. For the purpose of prosthesizing the central end of the humerus there are proposed the prostheses of the articular head and metaepiphyseal portion of the humerus made of metal or plastics (cf., e.g., aprospectus of the firm Vitallium, USA). By their shape such prostheses follow the articular head of the humerus and are juxtaposed with the articular process of the scapula during surgical operation, without being fixed thereto.

A disadvantage of the heretofore proposed endoprostheses of the central articular head of the humerus resides in that these are not fixed to the articular process of the scapula. This makes the operated shoulder joint instable and badly restricts its mobility, since the operated arm is devoid of a point of support or fulcrum at the base thereof. Moreover, another disadvantage of the hitherto proposed endoprosthesis of the articular head of the humerus consists in that its articular surface is incongruent with the articular process of the scapula.

It is an essential object of the present invention to provide an endoprosthesis of the, shoulder joint, viz., a complete substitute of that joint, which is able to retain mobility and stability of the operated shoulder joint due to its being fixed to the scapular bone.

This object is accomplished in that endoprosthesis of the shoulder joint, according to the invention, incorporates a pin adapted to be fixed in the medullary channel of the humerus and is provided with a spheroidal head at the end thereof, and a shaped crown adapted to be fixed on the articular process of the scapula, and having a spherical socket adapted to interact with the spheroidal head of the pin to form an articulated joint therewith.

It is desirable that an endlong groove or slot be made in the pin for the osseous tissue to intrude thereinto. Besides, a hole may beprovided in the pin for a screw to attach the pin.

The pin may also be provided with holes for passing ligatures to fix the muscles of the shoulder girdle to the It is expedient that the shaped crown of the endoprosthesis of the shoulder joint has tongues on the walls thereof to fix the crown to the articular process of the scapula.

Besides, the shaped crown may be provided with holes for screws to attach it to the articular process. The walls of the shaped crown preferably have holes for the osseous tissue to intrude thereinto.

It is desirable, according to the invention, that the edges of the walls of the shaped crown be split by slits into separate segments which, when compressed, ensure that theosseous tissue of the articular process of the scapula get tightly embraced by the walls of the crown.

The shaped crown may have a flute for the tendon of the long head of the brachial biceps muscle.

An important feature of the herein-proposed endoprosthesis of the shoulder joint is its being firmly attached to the scapular bone by virtue of the crown head fitted over the articular process thereof. Such an attachment serves as a fulcrum for the humerus, is instrumental in rendering the operated joint stable, and allows mobility in the articulated joint due to the shoulder girdle muscles being attached to the movable portion of the endoprosthesis, viz., to the pin thereof.

In what follows the invention is exemplified by the disclosure of a specific embodiment thereof, to be taken in conjunction with the accompanying drawing, wherein:

FIG. 1 illustrates a general side-elevation, partly sectional view of the endoprosthesis of the shoulder joint according to the invention;

FIG. 2 is a shaped crown as viewed along the arrow A in FIG. 1; and

FIG. 3 is a shaped crown as viewed along the arrow B.

Reference being first made to FIG. I, the endoprosthesis of the shoulder joint comprises a pin 1 adapted to be fixed in the medullary channel of the humerus and having an endlong groove 2 for the osseous tissue to intrude thereinto and an open-end hole 3 for a medical screw to pass. The pin 1 has a curved neck 4 provided with oval bosses 5 having open-end holes for the ligatures to pass. The pin 1 terminates in a spheroidal head 6.

The endoprosthesis also incorporates a shaped crown 7 adapted to be fixed on the articular process of the scapula. The shaped crown 7 has a spherical socket 8 (FIGS. 1, 2) adapted to interact with the spheroidal head 6 (FIG. I) to form an articulated joint therewith.

The pin 1 is free to be disconnected from the shaped crown 7 so that to a single crown may correspond several different-length pins 1 but the same spheroidal head 6. This facilitates the surgeon to select the length of the pin 1 required for the'given operation.

Lateral walls 9 of the shaped crown -7 have perforations 10 for the osseous tissue to intrude thereinto. The edges of the lateral walls 9 are split into separate segments by slits 11 so as to allow the surgeon to easily deform the walls of the shaped crown 7, thus making them tightly embrace the osseous tissue when the shaped crown 7 is fitted over thearticular process of the scapula.

A flute 12 (FIG. 2) is provided on the shaped crown for the tendon of the long head of the brachial biceps muscle, as well as holes 13 for the ligatures to pass, and holes 14 with guide channels, the latter holes being arranged at different levels and adapted to fix the shaped crown 7 by screws to the substance of the articular process of the scapula.

The edges of the lateral walls 9 of the shaped crown 7 terminate in tongues 15 adapted to fix the shaped crown 7 to the articular process.

The herein-disclosed endoprosthesis of the shoulder joint may be applied for a complete prosthesizing of the shoulder joint in the cases of grave comminuted fractures of the head of the humerus, resection of the latter in case of tumoral or some other malignant processes, 1

in case of a flail shoulder joint due to its vitiation or deformation, as well as in ankylosis of the shoulder joint, with the result that the stability and mobility of the arm operated in the shoulder joint are ensured, the anatomical proportions remain unaffected, the operated extremity has a physiological fulcrum at the basis thereof due to its being fixed to the scapula, the axes of movements of the artificial joint correspond to those of the natural joint, and the anterior and posterior groups of scapular muscles are kept attached to the joint movable portion, whereby the active functions of flexion, extension, abduction, adduction and rotation of the shoulder joint are ensured. 7

Besides, the entire endoprosthesis is located in the bulk of the tissues and is reliably covered by a bulky muscular-layer, being firmly attached on every side to the scapular and humeral bones.

What is claimed is:

1. An endoprosthesis of the shoulder joint, comprising a pin for being fixed in the medullary channel of the humerus, said pin being provided at its end with a spheroidal head, and a shaped crown to be fixed on the articular process of the scapula and provided with a spherical socket for interaction with said spheroidal head of the pin to form an articulated joint with the latter, on passing said pin through said socket, whose outer diameter is less than the diameter of said head of the pin, wherein walls of said shaped crown have their edges split by recesses into separate segments which, when compressed, enable osseous tissues to be tightly embraced by said walls of the crown.

2. The endoprosthesis as defined in claim 1, wherein said pin has an endlong groove for osseous tissues to intrude thereinto.

3. The endoprosthesis as defined in claim 1, wherein a hole is provided in said pin for a screw to attach said pin to the humerus.

4. The endoprosthesis as defined in claim 1, wherein said shaped crown has holes for attaching screws for the latter.

5. The endoprosthesis as defined in claim 1, wherein said shaped crown has holes for osseous tissues to intrude thereinto.

6. The endoprosthesis as defined in claim 1, wherein said shaped crown has a flute for the tendon of the long head of the brachial biceps muscle.

7. The endoprosthesis as defined in claim 1, wherein said shaped crown has holes for muscle-fixing ligatures to pass. 

1. An endoprosthesis of the shoulder joint, comprising a pin for being fixed in the medullary channel of the humerus, said pin being provided at its end with a spheroidal head, and a shaped crown to be fixed on the articular process of the scapula and provided with a spherical socket for interaction with said spheroidal head of the pin to form an articulated joint with the latter, on passing said pin through said socket, whose outer diameter is less than the diameter of said head of the pin, wherein walls of said shaped crown have their edges split by recesses into separate segments which, when compressed, enable osseous tissues to be tightly embraced by said walls of the crown.
 2. The endoprosthesis as defined in claim 1, wherein said pin has an endlong groove for osseous tissues to intrude thereinto.
 3. The endoprosthesis as defined in claim 1, wherein a hole is provided in said pin for a screw to attach said pin to the humerus.
 4. The endoprosthesis as defined in claim 1, wherein said shaped crown has holes for attaching screws for the latter.
 5. The endoprosthesis as defined in claim 1, wherein said shaped crown has holes for osseous tissues to intrude thereinto.
 6. The endoprosthesis as defined in claim 1, wherein said shaped crown has a flute for the tendon of the long head of the brachial biceps muscle.
 7. The endoprosthesis as defined in claim 1, wherein said shaped crown has holes for muscle-fixing ligatures to pass. 